Semiconductor integrated circuit (IC) dies have multiple electrical contact pads which are connected through external electrical leads or thin film conductors to plug-in contacts which are surface bonded to other members on a printed circuit board. In production processes, tape automated bonding (TAB) has been employed where a strip of tape in reel form provides a plurality of groups of metallic parts and where each group includes interconnected finger contacts. These are connected at inner beam ends to die contact pads by soldering, compression bonding, or other means. The outer ends of finger contacts are bonded to a lead frame or outer metallic leads of the die package.
U.S. Pat. No. 3,689,991 shows a multi-layer tape wherein sets of finger-like leads are secured or formed by etching techniques on an insulative tape layer. Such insulative tape layer affords support for the thin leads during the die bonding and encapsulation process and partly remains part of the internal final assembly. Single-layer tape has also been employed which is similar to the multi-layer tape described above except that a thin copper foil is used without lamination to a polyimide layer alone or with an adhesive material. U.S. Pat. No. 4,234,666 shows TAB processing of thin, delicate copper foil including inner and outer gang bonding of the leads to the die and lead frame, respectively.
U.S. Pat. No. 4,259,436 illustrates a method of making a multi-layer tape carrier comprising a flexible tape of an insulation material and a metal foil adhering to the tape.
U.S. Pat. No. 4,380,042 discloses a TAB process including a lead carrier tape with or without a dielectric carrier and an internal stabilizing foil frame which, after inner leads are connected to die bonding pads, is pulled off the tape by applying a pull force on a tab to sever tear links adjacent the lead to die bond.
As can be seen, many of the above constructions employ a plastic film bonded to the metal foil tape to act as a mechanical carrier for the delicate leads of the tape metallization.